JPH0421484Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a device for attaching a backrest support rod to a chair, and more specifically, to a device for supporting a backrest support rod so as to be tiltable back and forth with respect to a seat plate support. This invention relates to a device for attaching a backrest support rod in a case where the present invention is used.

[Conventional technology]

The backrest support rod of a chair is usually formed into an L-shape when viewed from the side, and its vertical part stands up from the rear of the seat plate and the backrest is attached to it, while its lower horizontal part is attached to the seat plate support etc. By attaching it so that it can rotate, the backrest can be tilted backwards. In that case, conventionally
As disclosed in Publication No. 8293, a pair of left and right backrest support rods are arranged along the outer surfaces of the left and right side plates of the seat plate support, and the backrest support rods are connected to the left and right sides of the seat plate support. The pin was supported on the side plate, but this increased the length of the pin, making it easier for the pin to bend.In order to reduce the pin's bending, it was necessary not only to increase the diameter of the pin, but also to increase the pin's diameter. The lower end horizontal part of the backrest support rod is all exposed, resulting in a poor appearance.

In order to solve this problem, Japanese Utility Model Publication No. 13608/1983 discloses a technique in which a single backrest support rod is pivotally connected between the right and left side plates of the seat plate support as a prior art.

[Problem that the invention attempts to solve]

In this publication, the lower horizontal part of the backrest support rod is inserted into the approximately box-shaped seat plate support from the rear, and in this way, the lower horizontal part of the backrest support rod is not visible from the side. , since this also pivots the lower end horizontal part of the backrest support rod to the left and right side plates of the seat plate support, it cannot contribute to shortening the length of the pin, and the length of the pivot pin Since cotter pins are used to prevent them from coming off, there is a risk that objects may get caught on the cotter pins during transportation, packaging, etc., and the problem of deteriorating the appearance remains unresolved.

In addition, since the width of the single backrest support rod is smaller than the distance between the left and right side plates of the seat plate support, the lower horizontal tip of the backrest support rod can easily slide left and right along the pivot pin. This causes the backrest support rod and the backrest to wobble from side to side.
In order to avoid this, there is a problem in that it is necessary to separately provide guide members that sandwich the left and right side surfaces of the horizontal portion.

The purpose of the present invention is to solve the above two problems at once when attaching a backrest support rod.

[Means for solving problems]

Therefore, in the present invention, a top plate is fixed to the upper surface of the left and right side plates of a seat plate support formed in a substantially box shape with an upward opening, and the top plate has a pair of left and right support pieces on the inside of the left and right side plates. The horizontal part of the lower end of the backrest support rod, which is formed in an L-shape when viewed from the side, is cut and raised so as to protrude downward. The backrest support rod is inserted into the plate support, and the tips of the lower horizontal portions of the backrest support rod are rotatably supported by the left and right support pieces via pins, and the backrest support rod is urged upward to the seat plate support. It is equipped with a spring.

〔Example〕

Next, the embodiments of the present invention are shown in the drawings (Figs. 1 to 4).
In the figure, 1 is a seat plate supported by a leg 3 via a seat plate support 2;
1 and 2 respectively show the backrests attached via the backrest support rods 5.

The seat plate support 2 is formed into a substantially box-like shape with an open upper surface, and has horizontal flanges 6 attached to the lower surface of the seat plate 1 on the four peripheral edges of its upper end, and the left and right horizontal flanges of each horizontal flange 6 A step is formed in the middle part over an appropriate range from front to back, and a top plate 7 is welded to the horizontal flange portion 6a formed with the step, while a pedestal mounting pipe 9 is attached to a cylindrical portion formed at the center of the bottom plate 2a. is inserted, and the pedestal mounting tube 9 is welded to the top plate 7 and the cylindrical flange portion 8,
The pedestal fitted into the pedestal mounting tube 9 is supported by the leg 3.

The backrest support rod 5 is formed by bending a metal pipe with an oval cross-section into a substantially L shape, and has a vertical portion 5a that projects upward from the rear of the central portion of the seat plate 1, onto which the backrest 3 is attached. While installing, the lower end horizontal portion 5b is inserted into the seat plate support 2 through a guide hole 11 formed in the rear plate 2b of the seat plate support 2, and its tip is positioned below the top plate 7. A pin hole passing through in the left-right direction is bored at the tip of the lower horizontal portion 5b.

The left and right side plates 2c of the seat plate support 2 at the rear part of the top plate 7 from the pedestal mounting pipe 9,
2c, a pair of left and right support pieces 13, 13 are formed by cutting downward and forming holes in the support pieces 13, 13 so as to sandwich the tip of the lower end horizontal portion 5b of the backrest support rod from the left and right sides. By inserting the pin 15 through the passageway and the pin hole at the tip of the horizontal portion 4b of the backrest support rod, the lower end horizontal portion 5 of the backrest support rod is inserted.
b is configured to be freely movable up and down. Note that the pin 15 is secured by a snap spring 16. Further, the pin 15 is inserted from the left and right side plates 2c of the seat plate support 5, so that the pin 15 is inserted into the left and right side plates 2c of the seat plate support 5.
A through hole 17 is formed for insertion of the snap ring 16 and attachment of the snap spring 16.

Furthermore, a hole 18 was formed in the rear part of the bottom plate 2a of the seat plate support 2, and a bottomed cylinder 19 was inserted into the hole from above and fixed integrally, and the hole 18 was disposed inside the cylinder 19. The lower end horizontal portion 5b is compressed by the compression spring 20.
is biased upward.

In the above configuration, when a person sitting on a chair leans his or her body backward, as the backrest 4 is pushed backward, the lower end horizontal portion 5b of the backrest support rod 5 moves downward against the force of the spring 20. When it rotates and raises its body, the force of the spring 20 returns it to its original state. In this case, the vertical movement of the lower end horizontal portion 5b is guided by the guide hole 11, and the tip of the horizontal portion 5b of the backrest support rod 5 is sandwiched between a pair of left and right support pieces 13. Since they do not shift, the backrest support rod 5 and the backrest 4 are reliably prevented from shaking from side to side. Further, the vertical movement range of the lower end horizontal portion 5b is restricted by the guide hole 11.

In the second embodiment shown in FIGS. 5 and 6, instead of forming a hole in the support piece 13, a notch 21 with a downward opening is formed. A pin 22 is fixed to the groove 21, and the pin 22 is engaged with the notch groove 21. In this case, the backrest support rod 5
The backrest support rod 5 can be installed by inserting it through the guide hole 11 with the lower end horizontal portion 5b facing diagonally downward and fitting the pin 22 into the notch groove 21 from below, so the installation work is easy. In addition, there is an advantage that there is no need to drill through holes 17 for pin insertion in the left and right side plates 2c of the seat plate support 2 as in the previous embodiment. Note that since the lower end horizontal portion 5b is urged upward by the spring 20, the pin 22
It never goes away.

The third embodiment shown in FIGS. 7 and 8 is a modification of the second embodiment, in which a pin 22 is welded to the tip of the lower horizontal portion 5b of the backrest support rod 5, and a pin 22 is welded to the tip of the lower horizontal portion 5a of the backrest support rod 5. A cutout groove 23 with a front opening is cut out at the tip of the support piece 13, and the supporting piece 13 is sandwiched between the left and right inner surfaces of the cutout groove 23. Note that this third embodiment can also be applied to the first embodiment. That is, a pin hole may be formed at the tip of each support piece 13 and the lower end horizontal portion 5b, and the pin 22 may be inserted into the hole.

[Functions and effects of the idea]

As described above, in the present invention, since the lower end horizontal portion of the backrest support rod is located inside the left and right side plates of the seat support, the lower end horizontal portion is completely invisible from the outside of the side surface of the chair.

A pair of left and right support pieces formed by cutting and raising the top plate fixed to the upper surface of the left and right side plates of the seat plate support body protrude downward from the inside between the left and right side plates, and the pair of left and right support pieces. Since the lower horizontal portion of the backrest support rod is rotatably supported via the pin, the length of the pin only needs to be shorter than the length between the left and right sides of the seat plate support. The pair of support pieces also become invisible from the outside.

Therefore, according to the present invention, it is possible to make the pin small in diameter and short, and it also prevents accidents that occur when both the right and left ends of the pin or the supporting pieces protrude outward, i.e., when objects are accidentally pulled on the pin during transportation or packaging. This will ensure that such accidents can be prevented.

Moreover, the horizontal portion of the backrest support rod is restricted from moving left and right at the rear by a guide hole drilled in the rear plate of the seat plate support, and the tip of the lower horizontal portion is connected to a pair of left and right support pieces. Since the backrest can be restricted from moving laterally, there is also an advantage that there is no need to provide a separate guide member to prevent the backrest support rod and the backrest from wobbling in the lateral direction.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with FIG. 1 being a partial side view of the chair, and FIG. 2 being a cross-sectional view of FIG.
Figure 3 is a cross-sectional view of Figure 2, and Figure 4 is a cross-sectional view of Figure 2.
Fig. 5 is a perspective view of the tip of the lower horizontal part of the backrest support rod in the second embodiment;
FIG. 6 is a side sectional view of main parts in the second embodiment, and FIG.
The figure is a perspective view of the tip of the lower horizontal part of the backrest support rod in the third embodiment, and FIG. 8 is a sectional view of the main part of the third embodiment. DESCRIPTION OF SYMBOLS 1...Seat plate, 2...Seat plate support, 2a...Bottom plate of the seat plate support, 2b...Rear plate of the seat plate support, 2
...Horizontal flange of the seat plate support, 3... Legs, 4
... Backrest, 5 ... Backrest support rod, 5b ...
Lower end horizontal part of backrest support rod, 7...Top plate, 11
... Guide hole, 13 ... Support piece, 15, 22 ...
Pin, 20...spring, 21...notch groove.

Claims (1)

[Scope of utility model registration request] A top plate is fixed to the upper surface of both left and right sides of a seat plate support formed in a substantially box shape with an upward opening, and a pair of left and right support pieces are attached to the top plate on the inside of the left and right sides of the seat plate support. The lower end horizontal part of the backrest support rod, which is cut and raised to protrude downward and is formed in an L-shape in side view, is inserted into the seat plate through a guide hole bored in the rear plate of the seat plate support. The backrest support rod is inserted into the support body, the tips of the lower horizontal parts of the backrest support rod are rotatably supported by the left and right support pieces via pins, and the backrest support rod is urged upwardly against the seat plate support. A device for attaching a backrest support rod to a chair, characterized in that it is provided with a spring.